Traction-engine.



G. L. CAMPBELL a. B. K. POSTLETHW'AITE.

TRAGTION ENGINE.

.APPLICATION FILED 11:13.16, 1911.

1 ,058,546. l v Patented Apr. 8, 1913.

4 SHEETS-SHEET 2.

DUI] mon/JEVS.

G. L. CAMPBELL 6L B. K. PSTLETHWAITE.

TBAGTION ENGINE.

APLIOATION FILED 1113,16, 1911.

. .lllllllllll H.; l

nummwim/5885s MMV/M Patented Apr. 8, 1913.

4 BEEBTB-BHEET 4.

PATENT onirica.

. `GrUY L. CAMPBELL AND BERKLLEY .KING POSTLETHWAITE, "'.MINNEAPLI MINNESOTA.

mc'rxoN-ENG'INE.

`Specification.off-lLettel-s Iatent.

APatented. Apk-8, 1913.

' vide van'engine of the character described,

having a plurality of carrying wheels 'and' a belt-like bediior increasing the ground sur- 'face contact; to provide an Vengine, .of the character mentioned with means :for 'augmenting the traction pull of the driving v'vheels-iandl witlihauling devices of suitable construction and arrangement; and topro-l vide a frame and supportingwheelstherefor 4arranged to exibly accommodate the wheelstojthe' road bed, and. to dispose the` hauling-strain directly yupon the axles of the traction wheels.

-ne embodiment et the present invention sidisel-usedl in the structure illustrated in the accompanying drawings, in whichilike characters of Vreference denote corresponding partsiin all the views, and in which-.-

Figure 1 is a side elevation of an enginev Acinistructerl and arranged in accordance with l the present intention; Fig. 2 1s a top plan view oit the saine, the superstructure being. removed; andy one set. of driving 'wheels being shuown in section, the section -being taken on the line 2-2finFig 3; Fig. 3 is a front end elevation et a traction engine constructed and arranged in .accordance with the present invention; Figli isa detail view in rearelevatiom showin-g the arrangement of the engine, chassis frame and traction mechanism; Fig. 5 isa detail view, on an -en- .larged scale and in side elevation, showing ,the side framing ybeams of the chassis andl in' conjunction therewith the vcarrying axles and Adraw bar; Fig-6 is a detail vview in hori- Zontal section, taken on the line 6-6 in Fig.

5; Fig. 7: is a detailvview in perspective ai a bearing box for the carrying axles; and" Fig,.8 is a detaii view onan enlarged scale,

vshowing a fra ent 'of a carrying axle-and a bearing box t erefor, the bearing box being show-n in vertical section.

A tractor constructed and arranged in accordance'with the present invention comprises a. plurality of mechanical elements, which may b'e best grouped their more inx timate or interdependent relation. i groups referred-to may 4be generalized under the headings -fas -`follows:.-The traction i mechanism, com-prisingtheuneans for carryiing'andpro elling the engine, and the transimission mec `anism necessary toc'onnect the l traction mechanism with the prime mover 'The cable traction, Imechzmism',` comprising ithe means for propelling the engine, using iin conjunction therewith an anchored ,cable -The drivingmechanism z-The steeri ing mechanism :-and, The hauling devices.

The traction mechanism- As lshown 4in lthe` accompanying drawings, the traction :mechanism is `provided with the-'endless belt bed, the plate. links l5, 15 whereof'are, as -`shown, rectangular i-n form Vand each pro- =vided with a central opening 16 for the reprojections 17 are extended from the elly of the-wheels 18, 18. are disposed in paired arrangement and are rotatvely mounted on the rounded ends '19 of the squared axles20. 'The axles 20 -are are `mounted in boxes 21, the vflang'es'22, 22 whereof straddle a bolster frame 23 in guided relation'thereto. The boxes` 2l, 21 `are constructed to a shorter dimension than the length ofv the openings 24, 24 in the -ends of the bolster frame-23, and larger of the said bolster.l The purpose of the a1*- rangementl is that by adjusting the plates 21 the axles 20, 20 may be vdisposed in closer ;or Vmore, separated relation.

The bolster 23 is rigidly bolted to side bars I27 of the chassis or frame of the tractor. The bolster is provided with s ring vgu s 428,28 arranged to receive in hoding Vre tion the springs 29, y29. rllhe springs 29 vrest upon equalizing bars 30, 130. Thenbars The vception of sprocket projections 17. Thev separated, as shown in the drawings, and` 26, 26l to the outside or inside of the boxes The wheels 18, 18

than the opening 25 formed at the center .30, are' shaped as best shown in Fig. 5

grally connected with the hub of the wheell 32, and form a space for the reception of the wheels 1 8, 18, as shown best in Fig. 2 of the drawings. The diameter of the wheels 18, 18 and 32 is the same, therefore i the tread of the three wheels, under normal conditions, is on the same level. The tread of the said wheels is upon the inner surface of the plate'links 15, 15. It will be understood that the wheel 32 has no rigid connection with the'plate links 15 or the traction bed formed thereby.

By reason of the arrangement of the carrying wheels as described the bearing of the wheels on the ground is amplified and the bearing points more nearly drawn t0- gether.

.Each of the wheels 18, 18 is provided with a sprocket wheel 34. The sprocket wheels 34 are Aixedly mounted on the hubs of the wheels 18, and are operatively connected by means of a chain 35. The chain 35 is extended between the said wheels 34 in engagement with the teeth thereof, and is passed under a sprocket wheel 3G`which is tixedly mounted on a driving shaft 37. ln its engagement with the sprocket wheel 36 the chain is held by an idler sprocket wheel 38 which is mounted on a shaft y39 between the members of a yoke 40. The yoke 40 is pivoted on a shaft 41 and is direct-ly connected with a pull spring, 42 attached to the tail end 43 of the said yoke 40. This construction provides a yielding slack absorber for the chain 35.

The driving shaft 37 is made in two pieces, centrally united by ,means offa diderential gearing. The differential gearing vis of usual construction, differing only in that for the usual gear teeth of the driving member thereof is substituted a worm gear wheel 44. Meshed with the teeth of `the worm gear wheel 44 is a worm 45 which is lixedly mounted on the driving shaft 46 of the traction mechanism. The' driving shaft 46 is engaged vwith the driving shaft of the driving mechanism by means of a clutch 47.

The operation of the' traction mechanism when the shaft 37 isrotated is as follows :V

theengine.' `Agathe groundfover which the engine is moving is irregular in surface,

-the bed formed by the plate links 15 is raised in contact with the central wheel 32, ro-

,tating the same and being held thereby in .the engine, the pulling strain of the chain 35 on the wheels 34, 34 is positive. By reason of the construction and mounting of the wheels 38, as shown in the drawings, any slack in the chain 35 will be taken up by the yoke 40 rocking on the shaft 41.. By reason of the differential gear connection of `the parts of the shaft 37 the speed of the Wheels on each side of the engine is accommodated to any curvature in the path of the said engine.

The cable traction mechanism-When, as sometimes occurs, the necessary propulsion for the traction engine is notobtained by the tractionmechanism, as, for instance, when operatingl over ground provided with a heavy undergrowth or where the ground is soggy or slippery, the propulsion is assisted by means of a mechanism for winding an anchored cable. When employing this method of propelling the engine the drums 49 and 50 are employed. The drulns 49 and 50 are constructed of different diameters, and are each ixedly mounted 011 dii'l'erent portions of the driving shaft 37. Under all conditions of this character a cable is carried forward to a point of anchorage and there secured. The free end of the cable is wound on one or other or both of the said drums as follows The drum 49 is preferably formed to a diameter Iexcess of'that provided by` Winding the cable on the drum 49, the. cable is wound upon the drum 50, which, being of much less diameter than the drum 49, exerts a greater leverage or pull on the cable. It will be observed in this connection that the traetion mechanism aids the pull on the drum O-to the extent represented by the' slipll pagefofthe plate links-, 15, it. being understood that thejrate of cable `winding is slower than the* tractiondri-ve of the i wheels 18. x

When a yet greater carriage propulsion force is required than that obtained by winding the cable upon the drum 50, this may be obtained by providing a' block pulley at the point of anchorage and in reeving the cable through the said block and' winding both free ends of the said cable on the two drums 49. and 59 and in opposite directions. These drums operating at different rates of speed, and the cable accom* modating itself to the rates of speed, a multiplied force .efiiciency is acquired at the expense of the rate of speed. When thus rigged the maximum .propulsive force f vprovided with balancing iy wheels 58, 53.

At each end of the crank shaft of the engine are provided the clutches 17 and 54. The operation and purpose of the clutch/17 is above described; that of the clutch 54- is y to operatively connect a. short shaft 55 with the said crank shaft. Theshaft 55 is provided with a bevel gear wheel 56 iixedly mounted on said shaft and meshed with a be'vel gear wheel.57. The gear wheel 57 is lixedly mounted upon a shaft 58 carrying `the driving pulley 59. The pulley 59 is used, as a rule, as ian auxiliar member, permitting the engine to be utilized as a power plant when the traction mechanism is not employed. The pulley 59 is also, at times, engaged when it is necessary to draw backward the engine, in which action the efficiency of the tractionmechanism is noty suliicient to start the engine, l

The controlling devices or mechanism usual tothe handling of engines of the character indicated are not shown in the accompanying drawings. Any suitable de vices may be employed.

The steering mechanism-The steering mechanism employed for guiding the en 'ne has an elongated tiller post 60. The tiller post 60 is set at an incline,"shown best in Fig. 1 of the drawings, and in this position is suitably mounted, and is provided at the forwardV and lower end with a worm 61. The worm 61 is meshed with a worm wheel 62. The wheel 62 is lixedly mounted on a shaft 63. The shaft 63 has ixedly mounted thereon a winding drum 64 'upon which is wound a cable or chain 65. The ends of the chain 65 are1 connected to eyelets' 66 formed onthe carrying axle 67 provided forf fthe steering wheels', 68. .f

The axle 67 is connected' with the bolster 69 by a -bal'l and socket joint 70. The ball and socket joint 70 thus formed permits the axle 67 andwheels 68 connected therewith to be deflected in the path of travel, and to rock transversely and independently of they frame of the engine. The -advantage vof groundis obvious. The chain 65 lends itself' lfreely to Athis action `on the part of the axle 67. l

The forward part of the frame of the engine resting on the wheels 68, 68 is provided with'a tank 71 and a bonnet 72. Suilii-l cient weight is imparted to the forwardend of the frame by this construction to cause the colter lange'73 on each of the said Wheels to sink into 'the ground, therebypreventing side slippage of the said wheels, and increasing the efliciency of the steering gear. yIn operating the steering gear the` tiller post 60 is rotated by 'means of a hand wheel" 74.

The hauling destaca-The hauling de-l vices shown in the accompanying drawsuch a construction in unbroken or heavyf ings consist of a spreader bar 75 which is' supported upon'the ends of draw bars 76, 76. The draw bars 76, as shown best in Fig.v 5 of the drawings, are pivotally connected at 7 7 to the holsters 23, 23. By means of`this connection it will be appreciatedithat thev pulling strain of the engine is initially received upon the axles of the driving wheels and the' housing therefor. In this manner the raking strain peculiar tothe employment of engines of this character is notv transmitted through the framing structure- Thus is a large proportion of the usual wear and tear of the framing structure avoided. The draw bars 76, 76 are supported by means of spiral springs 78, 78, these being disposed'in housings 79, 79. By thus supporting the dra'w bars 76 theyare permitted to yield to down pulling strains which other- Wise might be exerted upon the frame of the machine to lift the forward end thereof and vthe steering Wheels from ythe ground. As shown best in Fig. 2l of the drawings the spreader bar 75 is reinforced and braced by means of tie rods 80, 80 and turn buckles 81, 81 formed on the said tie rods. Having thus described our invention, what we claim as new and desire to secure -by Letters Patent is tf A traction engine, comprising a carrier frame having vertically disposed guide members; a plurality of carrying axles havingy of the engine; a plurality of traction Wheels having sprocket members extended from the periphery of sai'd Wheels rotatably mounted l on sald axles; a drivin mechanism embodying a prime mover and a plurality of chain connected sprocket Wheels Xedly mounted on said traction Wheels; and a plurality of traction belts extended around said traction Wheels provided with recesses to reeeive the sprockets of said wheels.

In testimony whereof We have signed our of two subscribing Witnesses.

GUY L. CAMPBELL.

BERKLEY KING POSTLETHWAITE. Wltnesses L. C. SIMoNs, G. H. GREAVES. 

